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  • Koskenkorva, Tiina (2012)
    Elucidation of transporter- and/or metabolic enzyme-mediated drug interactions is important part of early drug development. However the knowledge about clinical consequences of transporter-mediated drug-drug interactions is still limited and more investigation is needed to improve our understanding. MDR1 transporter, widely distributed on the pharmacokinetic barriers in the body (e.g. intestine) and has been shown no limit the bioavailability of drugs. Substrates of MDR1 are exposed to limited intestinal drug absorption and intestinal drug-drug interactions due to inhibition of the transporter. In predicting the clinical significance of an interaction, the principal obstacle has been the limited ability to appropriately scale the preclinical data into in vivo situation. In vitro-in vivo correlations on the extent of MDR1's influence on absorption and standardized predicting methods for drug-drug interactions using the inhibitory constants (IC50 and Ki) would greatly increase the value of in vitro studies. Current in vitro and in silico methods for prediction of the influence of MDR1 on intestinal absorption and related drug-drug interactions are discussed in the literature review. In addition, the latest regulatory draft guidances (FDA, EMA) are reviewed. Aliskiren has been shown to be a sensitive MDR1 substrate in vivo and high affinity substrate for the transporter in vitro. The objective of the experimental work was to study the MDR1-mediated transport of aliskiren and the related drug-drug interactions in vitro and in silico. Vesicular transport assay was used to obtain kinetic parameters for aliskiren (Km and Vmax) and inhibitor potencies (IC50) for ketoconazole, verapamil, itraconazole and its metabolite hydroxyitraconazole. Ki was further calculated for itraconazole and hydroxyitraconazole. Aliskiren showed high affinity to MDR1 transporter with a Km value 5 µM, consistent to what was reported previously in different assay systems. The interactions between aliskiren and the inhibitors in vitro correlated to the observed interactions in vivo in humans. In addition, hydroxyitraconazole was shown to be a potent inhibitor of MDR1-mediated transport of aliskiren in vitro. This suggests that hydroxyitraconazole may contribute to the pronounced interaction observed between aliskiren and itraconazole in a clinical interaction study. A compartmental absorption and transit (CAT) model with added enterocyte compartments and MDR1 efflux was used to describe the influence of MDR1 on intestinal absorption of aliskiren in humans. The integration of kinetic parameters (Km) from in vitro studies requires further optimization on how to describe the intracellular drug concentrations in the model. Aliskiren is however suitable MDR1 probe substrate to be used in in vitro and in vivo trials in humans and therefore gives a good basis for developing vitro-in vivo predictive models.
  • Tepponen, Tuomas (2017)
    Multidrug resistance protein 1 (MDR1, p-glycoprotein) belongs to the ATP-binding cassette transporter family and it's encoded by ABCB1/MDR1 gene. It is a protein which transports many different kinds of compounds out of cells, for example from endocytes to the lumen with the use of energy from ATP. MDR1 is there for a restrictive factor for several orally administered drugs. It`s important to have knowledge about MDR1-inhibitors, in order to avoid harmful drug-drug and food-drug interactions that might affect medical treatment. The purpose of this master's thesis was to optimize an in vitro MDR1-vesicle uptake method and use it to screen inhibitors from compound libraries. To optimize the method, the effect of cholesterol loading on ATP-dependent transport of test substrate N-methylquinidine (NMQ) was evaluated, transport kinetics of the vesicles and kinetics of known inhibitors were also tested. With the optimized method, screening was done with a library of 25 food additives and a library of 42 synthetic compounds. The chemical structures of the synthetic compounds were analyzed manually in order to find factors that could explain their ability to inhibit MDR1. Only one inhibitor was found among food additives: curcumin. Other additives didn't increase or decrease the ATP-dependent transport of NMQ. Several inhibitors were found from the library of synthetic compounds, also a couple of compounds were found to increase the active transport of NMQ. Results indicate, that the additives used in this study have low risk to cause MDR1 mediated interactions, if curcumin is excluded. The inhibitory effect of curcumin should be investigated in in vivo-situation, because vesicle-based in vitro-results have tendency to overestimate results. Screening results of the synthetic compounds gives more confirmation to the usefulness of the screening method. The MDR1-inhibition screening method described in this Master`s thesis is valid, and it can be used to screen different compound libraries for MDR1-inhibitors. In the future it could be used to screen different kinds of compounds, which might end up inside humans and cause interactions with drugs.
  • Puustinen, Sanna (2011)
    Drug-drug interactions occur when a drug or a drug metabolite modifies the activity of a drug metabolizing enzyme. As a result the concentration of active drug can be too low to be effective or too high and possibly toxic. This is an increasing problem in drug therapy where polypharmacy is rather common today. Therefore, in drug discovery and development significant efforts have been made in order to predict such interactions in advance and avoid them, or at least minimize them. This study is focused on medetomidine, a drug metabolized by UDP-glucuronosyltransferases (UGT). The aim of the study was to find inhibitors for medetomidine glucuronidation. Also the mechanism of possible inhibition was of interest. It is already common to test interactions of a given enzyme substrate with other enzymes of the same family either in phase I or phase II of drug metabolism in humans. It is less common, however, to examine such interactions between enzymes of two different families. In the present study it is tested if the compounds which are possible inhibitors of cytochrome P450 monooxygenase (CYP) also inhibit UGTs. Inhibition of glucuronidation was studied with HPLC method previously developed for medetomidine glucuronidation. First glucuronidation of medetomidine was studied without inhibitor compounds. After that the impact of three possible inhibitors on medetomidine glucuronidation was studied and results were compared with the initial results. Three compounds were found to inhibit glucuronidation of medetomidine. Also an interesting change in UGT's enzyme kinetics after the binding of inhibitor was discovered. It is interesting that same compounds could inhibit both CYPs and UGTs. The results revealed that if a CYP and a UGT could bind for the same compound, it is also likely that structural analogues of that compound will interact with both enzymes. In drug discovery and development it is important to take into account both CYP-enzymes and less studied UGTs, and their possible interactions.
  • Jansson, Teresa (2019)
    Conditional reimbursement was introduced in Finland in January 2017 as a temporary addition in the Finnish Health Insurance Act. An agreement can be made between a marketing authorisation holder (MAH) and the Pharmaceuticals Pricing Board. Conditional reimbursement status can be allowed for a medicinal product if the drug is addressing unmet medical need and there are uncertainties associated to the medicinal product considering i.e. therapeutic value or cost-effectiveness, when traditional reimbursement procedures are not suitable. Risk-sharing is an essential part of the agreements and the results are monitored. Types of agreements are divided into financial- and performance-based agreements. Conditional reimbursement in Finland has not yet been studied in a large extent since its introduction. The aim of this study was to create an overview of the medicinal products with conditional reimbursement in Finland, how the unmet medical need is addressed, and which treatment options are available. Also, benefits and risks of the different stakeholders of risk-sharing agreements (RSA), why these agreements are worth to implement, earlier experiences from the European Economic Area (EEA) countries and what pharmaceutical companies should consider prior to negotiations were investigated. A document analysis was performed for investigating the medicinal products with conditional reimbursement status in Finland. A systematic literature review was conducted for collecting information and earlier experiences of RSAs and managed entry agreements (MEA) in the EEA-countries. On February 1st, 2019 there was 19 medicinal products with conditional reimbursement in Finland. These drugs are successfully addressing unmet medical need. All stakeholders of RSAs encounter benefits and risks of these agreements but the MAH is the one carrying the largest responsibilities and risks. Risk-sharing agreements gained in popularity since the early 2000s in the EEA-countries. There is no golden standard for types of agreements made but MEAs are enshrined in legislation in most countries. The pharmaceutical company should as early as possible start shaping details and collect information of the product for which conditional reimbursement will be proposed to. Negotiations might be challenging, but the aim is an agreement in which both the MAH and the payer are content with. Finland is following a similar trend as other EEA-countries, since most of the medicinal products with conditional reimbursement are oncology medicines. The use of the drugs has been limited through reimbursement number codes for certain patients who are most likely to benefit from the treatment. Rationales for introducing RSAs in EEA-countries were similar, e.g. working with finite resources, improving access, reducing uncertainty and prices, managing budget impact and improving cost-effectiveness. It seems like Finland is unique by the temporary introduction of conditional reimbursement in legislation and in other countries it has been introduced as permanent. Starting the preparations early for negotiations could save time and resources. When a RSA is made and the medicinal product shows the benefits expected, this is the ideal situation where all stakeholders benefit.
  • Ukkonen, Anni (2020)
    The package leaflet (“leaflet”) is a technical document included in medicine packages to provide information about the medicinal product to the user. With the EU now encouraging the adoption of eHealth, it can be assumed that written medicine information would be included in the digitalisation process. Medicine users’ views on electronic forms of medicine information should be assessed before any changes can be made, but so far there is very little data on this. The aim of this study was to find out what kind of leaflet medicine users would prefer and how they would feel about an electronic leaflet. The main aim was to find out if there is a difference in preferences between different types of medicine users and between medicine users of different ages in the provision of a package leaflet. The study also sought to find out if the current leaflet is being read by medicine users. This study was conducted by carrying out a survey to pharmacy customers over the age of 16 collecting prescription medication(s) for themselves (n = 110). The data was collected at one retail pharmacy in Helsinki, Finland during July 2020. The data was analysed quantitatively. This study found that medicine users generally feel positively about an electronic leaflet (liked by 63%) and many are open to idea of an electronic leaflet (75%). The majority (88%) could see positives in using an electronic leaflet, regardless of leaflet preferences. The study did not find a difference between new and repeat medicine users in the preference for a particular leaflet format, but age is correlated with the preference for a particular leaflet type, with younger medicine users wanting an electronic leaflet as often as older medicine users want a printed leaflet. Having the leaflet appear in My Kanta pages after the medication has been dispensed was found to be the most popular way to receive an electronic leaflet. This study also found that there is a difference between new and repeat medicine users when it comes to reading the leaflet after a medication has been dispensed. With the current printed leaflet 81% of repeat medicine users and 38% of new medicine users do not read it. The most common reason given for not reading the leaflet was that the participant had read it before and did not feel the need to read it again. According to this study, medicine users, especially younger medicine users, feel positively about the idea of an electronic leaflet, which is encouraging for the future of an electronic leaflet. The results are in line with prior research, but also suggest that more medicine users feel positively about the idea of an electronic leaflet than before. The leaflet reading behaviours of medicine users also highlight the need for a system, where a medicine user can be alerted to any changes in the leaflet, which is something only an electronic system could do.
  • Kainulainen, Tuija (2015)
    The significance of OTC product sales has risen in pharmacies because of lower margins obtained from medicines and thus a fall in the revenue. Manufacturing enterprises must pay particular attention to the success of product launches to ensure that their products end up on pharmacy shelves instead of competitors. The study intended to determine if the known key factors of successful launch also apply when launching a product to pharmacy market and if any of these factors was thought to be the most important one from pharmacists' perspective. In addition it was researched if there would be some important factors to be considered exclusively in product launches to pharmacy market and which factors have the greatest impact on pharmacies decision making about the product selection. The study was conducted as a survey directed to pharmacists, in which just launched D-vitamin product Elivo Vahva+ D50 was used as an example product. As a second part of the study few participants were interviewed by e-mail. According to the study pharmacies are interested in products that fit their selection, in other words, they are proven to be effective and useful for customers. They should bring some added value to the existing selection, to be visually attractive, price-reasonable and with a large enough target group. Representative visits, product visibility in the media, as well as the customers demand have the greatest impact on pharmacies decision making about which products to include to the selection. In addition, belonging to a pharmacy chain often brings with it the obligation to keep certain products in the shelves. Least impact on the decision making was with the electronic newsletter and pharmacy events. Pharmacies profit margin, as well as the possible purchase discounts and OTC products compensation practices are also taken into account in selection decisions. It is important that the company invests in their representatives education and offer reliable product knowledge and sales arguments to pharmacies for example with personnel training or at least in the form of brochures. When deciding the timing of the launch, seasonal variations in sales as well as competitors market entries needs to be taken into account. If it's not possible to be the first in the market, the product needs to have a real added value compared to others.
  • Piipponen, Anu (2016)
    Pharmaceutical nanocrystals are under one micrometer sized crystals composed of pure active pharmaceutical ingredient (API) and stabilizer. Their apparent dissolution rate is improved compared to conventionally sized crystals. Rapid dissolution is mainly due to increased intrinsic surface area of API powder. Solubility increase is significant only with very small, under 100 nm crystals. Nanocrystal formulations with improved dissolution rates can be utilized to increase bioavailability of fairly insoluble BCS class II APIs. Few nanocrystal based products are already on market. Common methods for dissolution study of nanocrystals arecompendial dissolution apparatus 1 or 2, which usually rely on sampling and separation of undissolved fraction. The reliability of these methods is dependent of the separation efficiency. Unfortunately separation becomes more tedious with diminishing crystal size. Thus it would be desirable to replace the methods that require sampling and separation with methods that do not require separation of undissolved fraction (in situ methods), preferably with continuous detection. With the dialysis method the separation is easily achieved. However, the rate limiting step is not dissolution but diffusion through the dialysis membrane. Electrochemical in situ detection methods can only be applied to electroactive APIs. Utilization of in situ UV probes for monitoring nanocrystal dissolution is limited by the UV absorbance of the nanocrystals themselves. To date, light scattering methods have mainly been applied to solubility studies, with few attempts on dissolution studies. In this study the light scattering, dialysis and compendial paddle methods were compared for their ability to monitor the dissolution of indometacin nanosuspensions (NS). Light scattering experiments were performed with Zetasizer equipment. Three poloxamer 188 stabilized NSs, with average diameters (Dz) of 300 nm, 600 nm, and 900 nm, were evaluated. Dissolution studies were executed in sink conditions (under 30% of saturated concentration) and in slightly higher concentration (intermediate conc., 30-50% of saturated concentration) at pH 5.5. The compendial paddle method was performed on the same suspensions with the same medium at intermediate concentration. In the dialysis method the studied NS had a Dz value of 350 nm. The pH of the dissolution medium was 7.4, and the membrane was made of regenerated cellulose. Experimental results were fitted to exponential equation and the dissolution time DT, i.e. time to reach 99% dissolution, was determined based on the equation. In sink conditions the dissolution of all of the NSs was so rapid that reliable estimations of dissolution times could not be made with the light scattering method. In intermediate concentration the dissolution time (51±12 s) of the 300 nm NS was significantly lower than those of 600 nm (340±80 s) and 900 nm (230±50 s) NSs with a confidence level of 5%. The slowest dissolution of the 600 nm NS could be attributed to its broad crystal size distribution. With the compendial paddle method no significant differences in dissolution times could be detected. Compendial dissolution times, about 600-700 s, were markedly longer than those from light scattering experiments. The dialysis method was unable to discriminate between 350 nm NS and indometacin solution, which can be explained by rapid dissolution of the nanocrystals, followed by slow diffusion across the dialysis membrane. Of the studied methods, light scattering was the only one to discriminate between dissolution times of various NSs. It was most applicable to narrow crystal size distributions. It is a fairly small scale method requiring only 1 mL of dissolution medium and about 10 µg of nanocrystals. The method was not dependent on chemical analysis. Theost important limitation was the fact that due to the operational method of the Zetasizer, the first data point was not acquired until about 20 s after the measurement started.
  • Bruun, Tanja (2018)
    Marine organisms can be regarded as a diverse source of bioactive compounds with the possibility to discover novel drug lead molecules. Sea sponges produce bromine containing alkaloids, bromotyrosines, from which several are active against cancer. Some bromotyrosines have spirocyclic structure and the innate three-dimensionality and structural novelty of spirocycles make them an interesting option in drug design. Clavatadine C, extracted from sponge Suberea clavata, is a bromine containing spirocyclohexa-dienylisoxazoline alkaloid. It’s symmetric spirocyclic core can be viewed as a restricted derivative of open chain oximes, such as purpurealidin I, a bromotyrosine extracted from Pseudoceratina purpurea. Earlier work with purpurealidin I derivatives against melanoma cell line has had some promising results. Inspired by these earlier results, eight spirocyclic clavatadine C derivatives were synthesized according the published synthesis route. The activities of seven synthesized clavatadine C derivatives were tested on A375 melanoma cell line. All spiro derivatives were active with CC50 values ranging between 1.0 μM and 3.4 μM. Also, the activities of 10 earlier synthesized bromotyrosine derivatives were tested, from which four open chain oximes had CC50 values between 13.5 μM and 27.8 μM. Interestingly, the most active compounds were chlorinated and unhalogenated spirocyclic derivatives. In general, the spirocyclic compounds were 2- to 8-fold more active than the corresponding open chain oximes. The selectivity of active compounds was determined as cytotoxicity against Hs27 fibroblasts and by comparing the CC50 values of these two cell lines. The most selective compound was brominated derivative which had three times better selectivity against melanoma cells. The weak selectivity was consistent with the trend with open chain oxime analogs. Despite the selectivity issue, the improved activity of spirocyclic derivatives are promising and support for further investigation of marine-based spirocyclic bromotyrosine derivatives against melanoma.
  • Mankila, Anja; Mankila, Anja (2022)
    Cardiovascular diseases are the most common causes of mortality worldwide. More adequate human-based models would be needed for the purposes of disease modeling and drug development. One of the most promising fields of in vitro modeling is the use of human pluripotent stem cell-derived cardiomyocytes (hPSC-CMs). A central problem of hPSC-CMs is their immature or fetal-like phenotype compared to adult human cardiomyocytes regarding many structural, functional, and metabolic properties. The development of metabolic properties is considered to be a central driver of cardiomyocyte maturation. One practicable way to promote the metabolic maturation of hPSC-CMs in vitro is the use of various biochemical cues in the cell culturing media. The topic of this study was the metabolic maturation of hPSC-CMs. The research questions were: What biochemical cues have been suggested to be involved in the hPSC-CM maturation in vitro? What signaling pathways connected to the biochemical cues have been explored in the context of the maturation of hPSC-CM? What experimental results have been achieved on the effects of the biochemical cues and the involvement of the signaling pathways? The study was conducted as a systematic review with the database Scopus (Elsevier). The final set of materials consisted of 46 original research articles published in peer-reviewed journals in English in the years 2013–2022. Out of the materials, 11 articles (24%) were characteristically longitudinal studies. They indicated that the pathways leading to metabolic changes such as PPARs (peroxisome proliferator-activated receptors) and PGC-1α (peroxisome proliferator-activated receptor γ coactivator 1α) are activated already in early stages. In 12 articles (26%), pharmacological agents were used to target the metabolic pathways, and in 8 articles (17%) techniques affecting the gene expression were utilized. The most recent studies involved ever more frequently combinations of different techniques. Considering the use of biochemical cues, the trend has been to favor fatty acids, thyroid hormone and dexamethasone over glucose, insulin and insulin-like growth factor. Some cues such as retinoic acid and neuregulin 1 have been tested only in single experiments. In addition to the nuclear receptor mediated pathways, the energy sensors AMPK (AMP-activated protein kinase) and mTOR (mechanistic target of rapamycin), the oxygen sensor HIF-1α (hypoxia-inducible factor 1α), and the microRNAs turned out to be central.
  • Parviainen, Heli (2020)
    Statins are a commonly used group of drugs that reduce the cholesterol levels in blood and have been shown to reduce cardiovascular morbidity and mortality. However, a considerable percentage of patients experience adverse effects during statin treatment. Statin adverse effects have been associated with genetic polymorphisms and drug-drug interactions that affect the elimination and active transport of these drugs. A more comprehensive knowledge of statin metabolism may be a step towards better management of statin treatments. Statin metabolism both in vivo and in vitro has been subject of study for years. In vitro incubation conditions may considerably affect the observed clearance, and results obtained with different methods or in different laboratories may not be directly comparable to each other. No single in vitro study on a wide panel of statins has previously been conducted. Six statins and some of their metabolites, fourteen compounds in total, were included in the study. The intrinsic clearance (CLint) of these molecules was investigated in vitro on human liver microsomes (HLM) and a panel of eleven cytochrome P450 (CYP) enzymes recombinantly expressed in E. coli. Observed CLint values for each compound in HLM and for each compound-CYP pair with observed depletion were calculated. The percentual contributions of each CYP enzyme to the metabolism of the compounds was calculated. The results obtained with recombinant CYP enzymes (rcCYP) were complemented with studies on HLM with specific chemical inhibitors of CYP enzymes. In this study the metabolism of statin lactones seemed to be faster than the metabolism of the corresponding statin acids. Atorvastatin lactone, 2-hydroxy atorvastatin lactone, 4-hydroxy atorvastatin lactone and simvastatin were extensively metabolized. Atorvastatin, 2-hydroxy atorvastatin, 3R,5S-fluvastatin, 3S,5R-fluvastatin, pitavastatin lactone and simvastatin acid showed intermediate metabolism. 4-hydroxy atorvastatin, pitavastatin, pravastatin and rosuvastatin rates of metabolism were below quantification limit. CYP3A4 had a major role in the metabolism of atorvastatin and its metabolites, simvastatin and simvastatin acid. CYP3A4 also had activity towards pitavastatin lactone. CYP2C9 had a high activity towards both 3R,5S-fluvastatin and 3S,5R-fluvastatin. CYP2D6 may play a part in the metabolism of pitavastatin lactone. CYP2C8 may have some activity towards simvastatin and simvastatin acid. The data is mostly in agreement with previous in vitro and in vivo studies regarding both the metabolism rate of statins and the contributions by different CYP enzymes to the metabolism of statins. Due to the screening nature of the study and some methodological constraints, these data should be considered as preliminary and require confirmation in further studies.
  • Hyttinen, Nea (2023)
    Chronic wounds are a worldwide health problem that produce a lot of costs for society and can have a substantial impact on patients’ quality of life. Human adipose stem cells (hASCs) have been studied as a treatment option for chronic wounds as they can induce wound healing in many ways. Extracellular vesicles (EVs) produced by hASCs are a great solution to acquire the benefits of hASCs while avoiding their problems such as possible mutagenicity. HASC-EVs have been found to induce wound healing by for example enhancing angiogenesis and fibroblast proliferation. HASCs can be grown in 2D where the cells attach to the bottom of the cell culture vessel or in 3D where the cells attach to each other and create a spheroid. 2D cell culturing is easy and inexpensive but 3D cultured cells resemble in vivo –like conditions more. Because of these in vivo -like features, hASCs grown in 3D might produce EVs that resemble the properties of host cells in natural environment more than 2D. The aim of this thesis was to compare 2D culture, matrix-based nanofibrillar cellulose (NFC) hydrogel culture, and matrix-free suspension culture in ultra-low attachment (ULA) wells as growing platforms for hASCs and as continuous EV production methods. During culturing, the conditioned media was collected after which, the EVs were isolated, and the EV concentration and size range was measured with nanoparticle tracking analysis (NTA). After culturing, the metabolic activity of hASCs was measured and the cells were collected for immunocytochemistry (ICC) assay, western blot (WB) assay, and for quantitative PCR (qPCR) to examine the stemness and differentiation of hASCs grown in different cell cultures. The hypothesis of this thesis was that the NFC cell culture would produce the best EV yield and the best EVs for therapeutic use. Based on the acquired results, this hypothesis could not be supported. When visually inspecting the cells, all three cell cultures were viable but the metabolic activity of hASCs in NFC hydrogel was low compared to 2D and suspension cultures. Also, the EV, protein and RNA yield were lower in NFC. ICC, western blotting, and qPCR results were inadequate to make a straightforward implication of what cell culturing condition is the best for EV production and they would need repetition and optimization. Looking at the overall results, 2D cell culturing produced the best EV and RNA yield, had the highest metabolic activity and was least laborious cell culturing method which makes it a good option for continuous EV production. Suspension culture on the other hand resembles in vivo -like environment which could possibly produce better EVs for therapeutic use. The metabolomic assays on the EVs would be interesting to perform in the future to examine if the in vivo –like features affect the quality of EVs.
  • Räisänen, Titvi (2023)
    A clean area is an area isolated from its environment to prevent contamination of final product during aseptic processing. The clean area can be divided into four different grades from A to D, which all have different cleanliness standards. Grade A is the highest grade where preparing products that are not terminally sterilized must be performed. Airlocks are located between different grades to prevent free airflow, and enable necessary precautions, such as putting on protective garments and disinfecting material surface. These procedures reduce risk of contamination of the higher grade. The purpose of this study was to create a protocol to help evaluate material disinfection and transfer processes in the hospital pharmacy of Turku University Central Hospital and to determine surface bioburden of material stored in the grade C area. Surface samples of the examined material were taken in accordance with in-house guidelines by using contact plates and swabs depending on the surface of the material examined. After incubation, colony forming units were counted. Samples were taken from primary packages of ingredients and equipment stored in grade C area, as well as from material transfer boxes and cut flush plastic folders used in the clean area. Samples were taken both before and after routine disinfection of this material. 45 % of the samples taken before disinfection were contaminated. The lowest contamination rates were observed from items made from glass and those that were stored in their secondary package. In five plates grew more than 25 colonies, of which two had biofilm covering the whole surface of the plate. These samples were taken from larger plastic items, such as an infusion bag and a plastic folder. High bioburden is possible on the surface of material stored in grade C clean room, despite precautions. 25 % of the samples taken after routine disinfection were contaminated with a maximum of two colonies per plate. Despite disinfection, viable microbes may remain on the surface of material. Material with risk of high bioburden were selected for the protocol. Items were disinfected and transferred to grade B area as a simulation of normal processes. Different operators performed the protocol a total of eight times. 14 % of samples were contaminated with a maximum of two colonies per plate, except for one plate with 15 colonies. This repetition exceeded the limits set for the protocol. One repetition had zero contaminated samples. The bioburden of material surface after disinfection is affected by operators, cleanliness of the grade C area, and manipulation of the storage. A high bioburden increases risk of unsuccessful disinfection, and recontamination is possible in a non-sterile environment. Bacillus and Staphylococcus -species were identified from the samples taken during the protocol. Bacillus-species are usually isolated from soil, can tolerate harsh and low nutrient environments, and can form spores. Staphylococcus-species are part of the human skin microbiome. Microbes inside clean area are originated from personnel or surface of material transferred there. Material surface bioburden creates a contamination risk of aseptically prepared products, and thus material transfer and disinfection are critical stages during aseptic processing.
  • Pessi, Jenni (2013)
    Polymer microspheres hold great potential as oral drug delivery system for therapeutic proteins. Microspheres prepared with biocompatible and biodegredable polymers have been extensively studied, since the oral delivery of therapeutic proteins is challenging due to the conditions in the GI-tract. The aims of this research were to apply microfluidics on polymeric microsphere preparation process, to determine what kind of formulations are suitable for this technology, to establish a controlled preparation process that produces advanced particles and to create a template for oral protein drug delivery. With microfluidic fabrication it is possible to gain control over the process and content of each droplet. However, finding suitable formulations for microfluidics is demanding. In this study, biphasic flow was employed to successfully produce double (W/O/W) emulsion droplets with ultra thin shells. Once the process and formulation variables were optimized constant droplet production was achieved. Flow rates used were 500 µl/h in the inner and in the middle phase and 2500 µl/h in the outer phase, respectively. Two formulations were selected for further characterization: 5 % poly(vinyl alcohol) in water in the outer phase, 3 % polycaprolactone in ethyl acetate in the middle phase and either 10 % or 20 % poly(vinyl alcohol) and polyethylenglycol (1:4) in water in the inner phase. All the particles were found to be intact and contain the inner phase, as verified by confocal microscopy. Further, the particles were monodisperse and non-porous, as observed by scanning electron microscopy. Particle size was found to be around 20-40 µm, variation in the particle size within one batch was small and the particles were stable up to 4 weeks. The encapsulation efficiency of the particles was remarkable; as high as 85 % loading of the model compound, bovine serum albumin. Particles released 30 % of their content within 48 hours. In conlusion, developing functional formulations for micfoluidic technology was possible, the microparticles encapsulated the model protein extremely well and all in all microfluidic technology had a lot of potential for droplet manufacturing for pharmaceutical applications.
  • Lifländer, Rami (2020)
    Throughout the history, there has been a wide selection of drugs developed for therapy of cardiovascular diseases (CVD). Despite a broad spectrum of different therapeutic strategies to deaccelerate and try to reverse the progression of cardiovascular diseases has been achieved, only a modest amelioration of the health of the CVD patients was achieved, as the mortality remains high by being the cause of nearly one in every three deaths yearly, myocardial infarction being involved in majority of these cases. Novel solutions are being studied to overcome this problem, one of them being nanoparticles, which may provide potential solution by carrying drugs to the desired location. Microfluidics technique may further improve the properties of nanoparticles, being a platform that allows the production of homogenous and repeatable batches that are non-dependent by the operator using it. In this thesis, it is described how microfluidics-based preparation of spermine-functionalised acetalated dextran nanoparticles co-loaded with a trisubstituted isoxazole and curcumin perform in physicochemical and in vitro experiments, in order to evaluate their potential in the application of ischemic myocardial injury therapy.
  • Lehto, Kristiina (2023)
    Migreeni on toistuvia päänsärkykohtauksia aiheuttava neurologinen sairaus, jonka esiintyvyys on hyvin laajaa – Suomessa migreeniä sairastaa lähes joka kymmenes väestöstä. Migreenin puhkeamisella on tutkimusten mukaan vahva yhteys genetiikkaan, ja migreenin hoidossa käytettyjen lääkevalmisteiden metabolia on oleellisesti sidoksissa geeneihin. Farmakogenetiikka tutkii tieteenalana, miten perintötekijät vaikuttavat lääkeaineiden aineenvaihduntaan ja niistä syntyvään lääkevasteeseen. Tässä tutkimuksessa tarkasteltiin migreenin estolääkkeenä käytetyn trisyklisen masennuslääkkeen, amitriptyliinin, metaboliassa esiintyviä mahdollisia geneettisiä eroja itä- ja länsisuomalaisten välillä. Tutkimus toteutettiin tarkastelemalla yli 10 000 Terveystalon Biopankin biopankkinäytettä, joista määritettiin kolmen CYP-entsyymin (CYP2C9, CYP2C19, CYP2D6) fenotyyppien esiintyvyys itä- ja länsisuomalaisissa. Tutkimustulosten mukaan eroavaisuudet fenotyyppien esiintyvyydessä itä- ja länsisuomalaisten välillä olivat maltillisia. Amitriptyliinin metaboliassa erityisen oleellisen CYP2C19 geenin osalta sekä normaalia hitaampi että hidas metabolia olivat yleisempiä idässä kuin lännessä. Hitaan metabolian riskinä on tavallista suuremmat plasmapitoisuudet ja siten lisääntyneet lääkevalmisteen haittavaikutusriskit. Näin ollen amitriptyliiniä tulisi hitailla metaboloijilla käyttää harkiten, aloittaa vaihtoehtoinen lääkitys tai pienentää aloitusannosta puoleen tavanomaisesta. Oikean annostuksen löytämisessä tulisi hyödyntää laboratorion pitoisuusmäärityskokeita. Lisäksi farmakogeneettisillä testeillä voitaisiin havaita mahdollinen geenien tarkempi polymorfia, ja siten varmistaa sekä turvallinen että tehokas yksilöllinen lääkehoito.
  • Peuraniemi, Tuukka (2012)
    The aim of this research was to evaluate the use of microfluidic paper-based devices (µPAD) in drug analysis. Micro total analysis systems (µTAS) channels are in the range of a few micrometers and are capable of performing all steps of a chemical analysis. The advantages of miniaturization are lower sample consumption and faster analysis time. µTASs are usually fabricated of glass, silicon or polymers and their fabrication requires cleanroom facilities and specific equipment. Paper offers an inexpensive and versatile substrate for µTASs. Paper wicks liquids and no external pumps are required. µPADs advantages over µTAS are its ease of use and inexpensive and simple fabrication. µPADs are fabricated by patterning hydrophobic barriers in hydrophilic paper. There are several fabrication methods for µPADs such as photolithography, cutting and methods based on the application of wax (etching, wax printing, wax dipping). In this research wax printing was selected as the fabrication method because it's simple, rapid and inexpensive. Wax was printed using Xerox Phaser 8560DN solid ink printer. After printing the wax was melted through the paper by heating the paper at 150 °C for 120 seconds on a hotplate. Thus the wax creates a hydrophobic barrier on the hydrophilic paper which channels the liquids flow. Owing to papers anisotropic nature the wax also spreads horizontally in the paper when heated, thus reducing the wax patterns resolution and making the pattern coarse. Wax printing is an inexpensive and simple fabrication method suitable for fabricating µPADs. Also liquids flow velocity and methods for controlling the flow rate were studied. By knowing the flow velocity, one can assure that the analytes and reagents reach the reaction site. Controlling the flow velocity enables the use of multiphase reactions or the use of multiple simultaneous reactions on the µPAD. The liquid flow velocity can be controlled by changing the hydrophilic channels width, reducing the average pore size by melting a layer of wax inside the hydrophilic channel or by changing the surface tension or viscosity of the liquid used. Colorimetric assays are the most commonly used detection methods in µPADs, but also electrochemical sensing and detection methods based on fluorescence are used. In this study direct and indirect fluorescence detection methods were studied. In the detection method based on direct fluorescence, fluorescein and coumarine derivates were studied. In indirect fluorescence amino acids fluorescamine conjugates, which were created in the paper, were studied. Level of the analytes detected in direct fluorescence detection was 10-13 mol in the range of visible light and 10-12 mol in the range of UV-light. Level of the amino acids fluorescamine conjugates detected in indirect fluorescence detection was 10-9 mol. According to our results the fluorescence based detection methods used in this study are suitable for drug analysis on µPADs.
  • Pöyhönen, Suvi (2017)
    Cortical stroke induces a chain of events that results in secondary injury in the ipsilateral thalamus. Inflammation is a key player in the delayed injury. Microglia, the resident innate immune cells of the brain, seem to have an important role in the initiation and maintenance of the inflammation. After infarct they are rapidly activated and start to proliferate and release proinflammatory cytokines. They may even phagocytose viable neurons, a phenomenon called "phagoptosis". Many studies, which have aimed at inhibition of the the detrimental function of microglia, suggest that inhibition of microglia might offer promising therapeutical targets. However, microglia are also involved in the resolution and the repair phase after infarct, which makes development of novel therapies challenging. The only approved treatment for ischemic stroke, a fibrinolytic agent, has a very narrow therapeutic time window. Thus, new treatments are urgently needed. Modulation of inflammation may offer a wider therapeutic time window. In this study, we investigated the effects of two potentially neurotrophic factors, CDNF (cerebral dopamine neurotrophic factor) and MANF (mesencephalic astrocyte-derived neurotrophic factor), as well as a specific vitronectin receptor blocker, cRGDfV, on the prevention of neuronal death in thalamus in a transient murine cortical stroke model. MANF and CDNF are proteins released during stress of the endoplasmic reticulum (ER). They have been shown to protect neurons during ER stress and to reduce the production of some proinflammatory mediators. The vitronectin receptor blocker has in vitro inhibited microglial phagoptosis. The treatments were administered as single injections to the thalamus 7 days after the stroke onset. CDNF and MANF alleviated functional deficits, but did not protect thalamic neurons from death or affect the accumulation of phagocytic microglia. cRGDfV neither enhanced functional outcome nor protected neurons from death. The mechanisms of action were not investigated. In addition, we investigated, whether the death of thalamic neurons in the cortical stroke results in sensitization to pain. Central post-stroke pain has been reported on stroke patients and it has been associated with the death or the disturbances in the function of thalamic neurons. However, in spite of significant reduction in the number of neurons in the ipsilateral thalamus and the increase in the accumulation of phagocytic microglia on day 30 after stroke, we did not observe any significant sensitization to pain caused by thermal or mechanical stimuli on days 3, 14 and 28 after stroke. In conclusion, transient ischemic cortical stroke doesn't seem to induce sensitization to pain. MANF and CDNF seem to alleviate functional deficiencies, but they do not protect thalamic neurons from delayed death.
  • Petäjäsuvanto, Piia (2023)
    Microcrystalline cellulose is a compactable, versatile, and popular excipient in tableting. Microcrystalline cellulose is produced using acid hydrolysis where most of the amorphous areas are removed and the crystalline part is left. Particle size affects most on the functionality of microcrystalline cellulose and that can be altered by changing the duration of acid hydrolysis or the drying method. The aim of this Master’s thesis was to compare new microcrystalline materials produced using energy efficient methods, to commercial Avicel-powders. The used formulation consisted of microcrystalline cellulose, hydroxypropyl methylcellulose, magnesium stearate and dried colloidal silicon dioxide. Due to the small particle size of AaltoCell™ samples it was not possible to use it for direct compaction, but with wet granulation this was successful. The tablets were tested by the standards of European pharmacopoeia and the tablets from wet granulated Avicel PH-101, AaltoCell™ sample B and C passed all the tests. Probably the problem with the rejected formulations was poor flowability, which caused poor reproducibility in the experiments with direct compressed tablets. The wet granulated Avicel PH-101 produced the best tablets with the used formulation.
  • Mäkinen, Jarkko (2014)
    Miniaturizing of analytical techniques in mass spectrometry has received a lot of attention amongst scientists. The gains of miniaturization of analytical systems are rapid analyses, lower solvent consumption, the option for automatization and lower costs. A glass-made microchip heated nebulizer and a newer version, steel-made nebulizer, have been recently developed. The aim of this study was to evaluate and compare performances of the nebulizers. Changes in test conditions and effects of different dopants to intensiveness of the analytes' signals were analyzed. Speed of nebulizer gas, speed of analyte flow and magnitude of heating were the parameters of the changes in test conditions. The temperature of the flow from the nebulizers was also measured and analyzed. The intensiveness profiles of the analytes between the nebulizers were unequal, when changes in the speed of nebulizer gas and magnitude of heating were measured. The nebulizers reacted the same way to changes of the speed of analyte flow. The faster the analyte flow was, the more intensive the analytes' signals were. The steel tube nebulizer generated on average more intensive signals of the analytes than glass-made microchip. Temperature of the glass-made nebulizer was considerably higher than that of steel tube nebulizer. The most intensive signals of the analytes were achieved when toluene was used as a dopant. Steel tube nebulizer was more efficient in ionizing analytes than glass-made microchip. However, with steel tube nebulizer it could be difficult to analyze compounds with high boiling point. One goal of this study was to combine the steel tube nebulizer with capLC, but due to technical failures of the capLC equipment this was not possible. In the future, it would be beneficial to improve the steel tube nebulizer's heating mechanism. Also it could be combined with other ionization techniques as has been done with glass-made nebulizer.
  • Kurvonen, Sampo (2019)
    Background: Antibiotics have been an important factor in the dramatic decrease of infectious disease mortality in the 20th century. Bacteria are, however, very quick to respond to the changes in their environment because of their short life cycle. Thus, the development of bacterial antibiotic resistance is a natural consequence of the enormous worldwide antibiotic use. The current situation is that the antibiotic resistance develops faster than novel antibiotics are found and developed. The three main resistance strategies of Gram-negative bacteria are: modification of the antibiotic target, enzymatic inactivation of the antibiotic and reduce of the intracellular antibiotic concentration by changing the function of the outer membrane. To decrease the intracellular antibiotic concentration bacteria use efflux pumps. RND efflux pumps are the most important family of efflux pumps regarding antibiotic resistance. They typically function as a part of a tripartite structure which allows the efflux of antibiotics to the extracellular space. Multiple inhibitors have been developed against RND efflux pumps but none has reached the clinical stage of drug development. Objectives: Development and testing of a 384-well plate method for screening efflux pump inhibitors for E. coli (BAA1161) efflux pumps. Methods: Verifying that the absorbance measurement is a sensitive enough method for measuring the bacterial (BAA1161) growth in 384-well plate format. The antibiotic chosen to be used in the screening method was piperacillin and the positive control efflux pump inhibitor was mefloquine. Determining the minimum growth inhibiting concentrations (MICs) of piperacillin and mefloquine in 96- and 384-well plate formats. Verification of the synergistic growth inhibitory effect of piperacillin and mefloquine with the checkerboard method in 96- and 384-well plate formats. Determining the positional effect in the 384-well plate. Determining the highest DMSO concentration without effect on the growth of BAA1161. Screening of 126 natural compounds in 384-well plates to test the developed method. Screening was done in quadruplicates based on the growth inhibitory effect of the natural compounds when combined with piperacillin. Dose-response assay was conducted in combination with and without piperacillin with the compounds that showed growth inhibiting effect during screening. Results and discussion: Absorbance measurement was sensitive enough method for measuring the BAA1161 growth in the 384-well plate. MIC value of mefloquine was 32 μg/ml in both plate formats. Piperacillin’s MIC was 1024 μg/ml in the 96-well plate, but on the 384-well plate there was variation in the MIC. Piperacillin and mefloquine showed synergistic effect on BAA1161 growth inhibition in the checkerboard assays. Positional effect could not be determined, because of the variation in the BAA1161 growth inhibition effect of piperacillin. This randomly occurring phenomenon were piperacillin inhibited BAA1161 growth completely or almost completely with sub-MIC concentration was encountered in all the subsequent experiments in the 384-well plate format. One possible reason for this phenomenon, occuring in the 384-well plate format, could be piperacillin heteroresistance of BAA1161 strain. In the test screen, four compounds, which all included gallic acid ester, showed promising activity. These compounds were: epigallocatechin gallate, hamamelitannin, isopropyl gallate and octyl gallate. In the dose-response assay, hamamelitannin’s and octyl gallate’s effect was synergistic with piperacillin. Conclusions: The developed method can be used to screen novel efflux pump inhibitors. However, to increase the reliability of the method, further optimization is required to eliminate the variability in the effect of piperacillin. When plate format of a method is changed, factors which could affect the functionality of the method in the new format should be carefully assessed. Based on the test screed, gallic acid esters are interesting compounds which combined effects with antibiotics should be studied in the future experiments.